Continuity mistake: As Kenny is riding the bike, to try and grab on to the ladder at the back of the camper, the rear side-marker light on the camper is missing its red lens cover. In subsequent shots the red cover is there, and then vanishes again.
Continuity mistake: During the chase through the gravel roads and the rock quarry the Trans-Am is following the Vette. In one scene the scrub brush can be seen breaking off the low-hanging front spoiler on the Vette. It is gone for the remainder of that particular location. However, once the car leaves the gravel road and is back on paved highway immediately following, and for the rest of the film, the spoiler is back in place as if nothing happened.
Continuity mistake: The custom fiberglass hood is delivered to the school, and Kenny rips the wrapping paper off immediately to examine it. The hood scoop molded into the hood is missing the large row of forward-facing vents that are there the next time the hood is shown.
Revealing mistake: The car has side-exit exhaust, or 'side pipes' as they are more commonly called. The characters also refer to them as 'Mercury tubes' several times throughout the movie. In the scene during the car chase out of Las Vegas, the Vette skids to a stop at the freeway dead-end sign. As the car accelerates away again, the actual functioning stock exhaust pipes can be seen exiting under the rear bumper and smoke can be seen coming out of them. The 'Mercury Tubes' aren't even hooked up.